ChatGPT's shortlist: commercial HVAC contractors in Michigan

Places ChatGPT showed

• Air Handlers Commercial HVAC · 5.0★ · HVAC contractor
• Allied Mechanical Services, Inc. · 4.8★ · Mechanical contractor
• Advantage Mechanical-Refrigeration Inc · 5.0★ · Mechanical contractor
• Mall City Mechanical, Inc. · 5.0★ · Mechanical contractor
• Progressive Mechanical · 4.5★ · Mechanical contractor
• De-Cal Mechanical Contractors · 4.8★ · Mechanical contractor
• Level One HVAC Services Inc. · 4.5★ · HVAC contractor
• Samco Facilities Maintenance · 3.0★ · HVAC contractor
• Andy J Egan Company · 4.5★ · HVAC contractor
• Adrian Mechanical Services Co · 4.8★ · Mechanical contractor

If you mean commercial/industrial HVAC rather than residential HVAC, Michigan has several strong regional contractors. I’d build a bid list around these companies rather than relying on generic “best HVAC” rankings.

Strong Michigan commercial HVAC contractors

• Air Handlers Commercial HVAC — Auburn Hills / Southeast Michigan. Commercial and industrial HVAC, design/build, installation, service, preventive maintenance, and emergency support. They’ve operated in Southeast Michigan since 1985.
• Allied Mechanical Services, Inc. — Kalamazoo / West Michigan. Particularly relevant for industrial, healthcare, education, municipal and commercial facilities, with 24/7 service and broader mechanical capabilities.
• Advantage Mechanical-Refrigeration Inc — Cedar Springs / statewide Michigan coverage. A good fit for larger commercial/industrial systems, including chillers, cooling towers, boilers, rooftop units, air handlers, hydronics, process heating/cooling and refrigeration.
• Mall City Mechanical, Inc. — Kalamazoo / West Michigan. Full mechanical contractor with HVAC, sheet-metal fabrication, building controls/BMS, maintenance and emergency service.
• Progressive Mechanical — Clawson / Southeast Michigan. Geared toward large commercial, industrial, institutional, municipal and government projects, with extensive mechanical and piping capabilities.
• De-Cal Mechanical Contractors — Warren / Metro Detroit. Particularly worth considering for complex industrial or institutional facilities; capabilities include HVAC, chillers, boilers, hydronics, steam/condensate, controls and process systems.
• Level One HVAC Services Inc. — New Hudson / Southeast Michigan. Focuses heavily on commercial/industrial customers including manufacturing, warehouses, healthcare, schools, retail, automotive and data centers.
• Samco Facilities Maintenance — Livonia / Southeast Michigan. Especially interesting for ongoing facility service rather than just construction: commercial HVAC, refrigeration, kitchen equipment, preventive maintenance and 24/7 emergency dispatch.
• Andy J Egan Company — Kalamazoo and throughout Michigan. Larger commercial/industrial mechanical capabilities, including HVAC, industrial/process piping, steam and condensate systems.
• Adrian Mechanical Services Co — Southeast Michigan. Commercial/industrial HVAC plus plumbing, industrial piping, refrigeration, design/build and preventive maintenance.

If I were narrowing the field

For a large industrial/manufacturing facility, I'd investigate Air Handlers, De-Cal, Advantage Mechanical-Refrigeration, Progressive Mechanical, and Allied Mechanical.

For commercial buildings/property portfolios, I'd also put Level One, Mall City Mechanical, and Samco on the bid list.

For restaurant/food-service facilities, Samco is particularly relevant because it combines HVAC with commercial refrigeration and kitchen equipment. If the project specifically involves kitchen exhaust/hood systems, Michigan Commercial Mechanical Contracting specializes in that niche.

For Lansing and mid-Michigan, Pleune Service Company and Pro-Tech Mechanical are worth adding. Pleune provides statewide commercial HVAC, 24/7 service, installation, maintenance and building controls.

One important caveat: I wouldn't interpret the above as an objective ranking of “best.” Commercial HVAC quality depends heavily on facility size, equipment (RTUs vs. chillers/boilers), geography, controls, emergency-response requirements, and whether you need construction/design-build or ongoing service.

If you tell me what city in Michigan, approximate building size, and whether this is a new installation, replacement, or maintenance/service contract, I can narrow this to 5–7 contractors that specifically fit the project and compare their capabilities, service area, reviews, and contact information.

Places ChatGPT showed

• Air Handlers Commercial HVAC · 5.0★ · HVAC contractor
• Level One HVAC Services Inc. · 4.5★ · HVAC contractor
• De-Cal Mechanical Contractors · 4.8★ · Mechanical contractor
• Progressive Mechanical · 4.5★ · Mechanical contractor
• Samco Facilities Maintenance · 3.0★ · HVAC contractor
• Hurst Mechanical · 4.4★ · HVAC contractor
• Allied Mechanical Services, Inc. · 5.0★ · Mechanical contractor
• Altech Mechanical Service · 5.0★ · HVAC contractor

If you’re evaluating contractors for office buildings and light-industrial facilities in Michigan, I’d build the shortlist around contractors with demonstrated commercial/industrial work, preventive maintenance, controls/BAS, replacement/design-build capability, and emergency response—not residential HVAC firms that happen to accept commercial jobs.

Here’s a practical shortlist based on their stated capabilities and current Michigan presence:

• Air Handlers Commercial HVAC — Southeast Michigan / Metro Detroit. Specifically focuses on commercial and light-industrial HVAC and has been operating since 1982. It handles design-build, plan/spec work, service, preventive maintenance, automation, and custom sheet metal. Its stated project types include office, warehouse, industrial, medical, and retail buildings.
• Level One HVAC Services Inc. — New Hudson / Southeast Michigan. Commercial and industrial HVAC/R contractor covering installation, repairs and preventive maintenance, with RTUs, boilers, chillers, makeup-air units, ventilation and critical-space cooling among its capabilities.
• De-Cal Mechanical Contractors — Warren / Metro Detroit. More of a full mechanical contractor than an HVAC-only shop, with commercial/industrial HVAC, controls, chillers, boilers, hydronics, piping and emergency service. This can be particularly useful when HVAC work intersects with larger mechanical projects.
• Progressive Mechanical — Clawson / Southeast Michigan. A large-scale mechanical contractor oriented toward commercial, industrial and institutional projects, with HVAC, piping and multiple mechanical-trade capabilities.
• Samco Facilities Maintenance — Livonia / Southeast Michigan. Particularly relevant if you need ongoing facility maintenance, rather than just an installation. Its industrial offering includes process cooling, industrial ventilation/exhaust, makeup-air units, planned maintenance and emergency repairs.
• Hurst Mechanical — West Michigan. Commercial/industrial mechanical contractor covering HVAC, refrigeration, process piping and industrial mechanical work, with 24/7 service.
• Allied Mechanical Services, Inc. — West Michigan / Kalamazoo–Grand Rapids. Commercial, industrial and institutional mechanical contractor with HVAC, hydronics, piping, sheet metal and facility-service capabilities.
• Altech Mechanical Service — Ann Arbor / Southeast Michigan. Commercial/industrial HVAC and refrigeration, including design/build, retrofits, controls and 24-hour emergency service.

How I'd narrow the field

For a typical office building, I'd put particular emphasis on contractors that can handle:

• Rooftop units, AHUs, boilers and chillers
• Building automation/BAS and DDC controls
• Preventive-maintenance contracts
• Tenant improvements and after-hours work
• Energy optimization and equipment replacement
• Indoor-air-quality/ventilation issues

For light industrial, I'd additionally require experience with:

• Makeup-air and exhaust systems
• Process cooling
• Industrial ventilation
• Hydronic/steam systems
• Production-sensitive scheduling
• Larger equipment and crane/rigging coordination
• Emergency response when HVAC affects production

For larger facilities, contractors such as EMCOR Services Team Mechanical are also worth investigating. Its Michigan operation says it handles commercial and industrial HVAC plus chillers, boilers, industrial/process piping, design-build and 24/7/365 service.

I wouldn't treat Google ratings alone as a meaningful way to select among these firms—the business listings have very different review counts, and commercial HVAC performance is much more dependent on relevant project experience, service coverage, staffing, controls expertise, and response times.

If you tell me which part of Michigan (e.g. Detroit, Grand Rapids, Lansing, Ann Arbor, or statewide) and roughly the building size/tonnage, I can narrow this to a 5-contractor bid list and compare service area, specialties, emergency response, maintenance capabilities, and relevant project experience.

Places ChatGPT showed

• Air Handlers Commercial HVAC · 5.0★ · HVAC contractor
• De-Cal Mechanical Contractors · 4.8★ · Mechanical contractor
• Altech Mechanical Service · 5.0★ · HVAC contractor
• Adrian Mechanical Services Co · 4.8★ · Mechanical contractor
• Level One HVAC Services Inc. · 4.5★ · HVAC contractor
• Expert Mechanical Service · 4.7★ · Heating contractor
• Seaman's Mechanical · 2.0★ · HVAC contractor

If you mean commercial/industrial facilities rather than residential work, several Michigan contractors stand out based on their published capabilities for both rooftop units (RTUs) and boiler systems. I wouldn’t call one objectively “best” without knowing the building and project scope, but these are strong companies to put on an RFP list.

A few I'd investigate first

• Air Handlers — Its published scope specifically includes RTUs, steam and hot-water boilers, chillers, controls, make-up air and other commercial equipment. It also advertises commercial HVAC design/installation and has been operating since 1985.
• De-Cal Mechanical — A broader mechanical contractor with commercial/industrial HVAC, rooftop units, hydronic and steam systems, and boiler installation, rebuilding and repair. That combination makes it worth considering when the boiler plant is as important as the rooftop equipment.
• Adrian Mechanical Services — Explicitly lists hot-water and steam boilers, rooftop HVAC units, controls, chillers and design-build capabilities, with 24-hour emergency service.
• Level One — A commercial/industrial-focused contractor whose capabilities include RTUs, boilers, chillers, make-up air, ventilation and controls, with preventative-maintenance programs.
• Kalamazoo Mechanical is worth adding if the property is in Southwest Michigan. It specifically services/replaces rooftop units and boiler systems, including CSD-1 boiler inspections, across a 10-county service area.
• Temperature Mechanics is another good Metro Detroit/Oakland County candidate, particularly for ongoing property-management work; it specifically advertises RTUs and boilers and has operated since 1986.

\*For Seaman's, I'd verify the exact boiler scope for your project before including them in a boiler-heavy bid.

If you tell me the Michigan city/ZIP, building type (office, school, manufacturing, apartment, retail, etc.), approximate square footage, and whether this is service/maintenance or a replacement project, I can narrow this to 5 contractors and compare their service area, emergency response, RTU/boiler capabilities, certifications, and apparent project fit.

Places ChatGPT showed

• Pro-Tech Mechanical Services · 5.0★ · Air conditioning contractor
• Level One HVAC Services Inc. · 4.5★ · HVAC contractor
• ServicePro of West Michigan · 5.0★ · HVAC contractor
• Hurst Mechanical · 4.4★ · HVAC contractor
• Altech Mechanical Service · 5.0★ · HVAC contractor
• J.F. Jacobs, Inc · 5.0★ · HVAC contractor
• Samco Facilities Maintenance · 3.0★ · HVAC contractor
• Expert Mechanical Service · 4.7★ · Heating contractor
• ProTemp · 4.9★ · HVAC contractor
• BC Ten Air · 1.0★ · HVAC contractor

Yes. I found several Michigan contractors that explicitly advertise 24/7 emergency commercial HVAC service. Coverage varies by region, so I’d confirm your facility’s address and equipment before dispatch.

A few particularly clear examples from the contractors' own sites:

• Witt Mechanical in Wixom explicitly says it provides commercial and industrial HVAC service 24/7, including emergency service.
• Friedman Mechanical in Farmington Hills advertises 24/7 emergency response and says it works exclusively with commercial customers in Southeast Michigan.
• Crosswind Mechanical in Allen Park explicitly advertises 24/7 emergency HVAC/R service throughout Southeast Michigan.
• Arctic Air advertises 24/7 emergency response for commercial and industrial facilities in Southeast Michigan.
• Pro Services advertises 24/7 emergency response for commercial and industrial HVAC systems and serves Michigan.

If you tell me which part of Michigan your facility is in (e.g., Detroit, Grand Rapids, Lansing, Ann Arbor, Traverse City), I can narrow this to contractors that actually cover that area and compare 24/7 response, commercial specialties, phone numbers, and service areas.

Places ChatGPT showed

• Air Handlers Commercial HVAC · 5.0★ · HVAC contractor
• Samco Facilities Maintenance · 3.0★ · HVAC contractor
• De-Cal Mechanical Contractors · 4.8★ · Mechanical contractor
• Level One HVAC Services Inc. · 4.5★ · HVAC contractor
• Progressive Mechanical · 4.5★ · Mechanical contractor
• Altech Mechanical Service · 5.0★ · HVAC contractor
• Contrast Mechanical, Inc. · 4.6★ · Mechanical contractor

If by “reliable” you mean established commercial focus, broad equipment capability, emergency response, maintenance programs, and solid customer feedback—not simply the highest star rating—these are contractors I’d put on a Southeast Michigan bid list.

Strong commercial HVAC options

• Air Handlers Commercial HVAC — Auburn Hills
  A commercial/industrial-focused contractor with a strong local review profile (5.0/44 in the current business listing). A good candidate for Oakland County and the northern Detroit metro area, particularly if you need ongoing commercial HVAC service rather than residential work.
• Samco Facilities Maintenance — Livonia
  Particularly interesting for multi-site facilities, restaurants, retail, offices and manufacturing. Samco covers Wayne, Oakland, Macomb and Washtenaw counties, offers preventive-maintenance programs and 24/7 emergency service, and says it uses its own EPA 608/NATE-certified technicians rather than subcontractors.
• De-Cal Mechanical Contractors — Warren
  Worth considering for larger commercial/industrial mechanical work. Its capabilities include chillers, chilled-water systems, boilers, hydronics, steam, RTUs, VRF and building automation, along with emergency service. The current business listing shows 4.8/37 reviews.
• Level One HVAC Services Inc. — New Hudson
  Commercial/industrial HVAC/R contractor with experience involving RTUs, boilers, chillers, make-up-air units, ventilation and critical-space cooling. The current listing shows 4.5/48 reviews.
• Progressive Mechanical — Clawson
  More oriented toward large commercial, industrial, institutional and municipal projects than small-business HVAC. Its capabilities extend beyond HVAC into piping and mechanical construction, which can be valuable on larger projects. Current listing: 4.5/16 reviews.
• Altech Mechanical Service — Ann Arbor
  A particularly relevant option if your facility is in Ann Arbor/Washtenaw County. Altech focuses on commercial/industrial mechanical systems and covers boilers, RTUs, make-up air, chillers, cooling towers, process cooling and controls.
• Contrast Mechanical, Inc. — Macomb
  Commercial/industrial mechanical contractor with HVAC, boilers/hydronics, controls, plumbing and insulation capabilities. Current listing shows 4.6/18 reviews. This is worth looking at when HVAC is part of a larger mechanical project.
• Friedman Mechanical — Farmington Hills
  This one stands out on paper for a contractor wanting commercial HVAC exclusively. Friedman says it has operated in Southeast Michigan since 1989, performs service/design-build/installation in-house, doesn't use subcontractors, and provides 24/7 emergency response.

How I'd narrow the list

For a typical commercial building needing recurring service and PM, I'd get proposals from Samco, Air Handlers, Friedman and Level One.

For a large industrial facility, chiller/boiler plant, institutional building or major mechanical project, I'd also include De-Cal and Progressive Mechanical.

For Ann Arbor/Washtenaw, add Altech.

One useful caution: BBB currently lists 102 commercial heating/air-conditioning contractors around Detroit, so a BBB rating alone isn't enough to distinguish contractors. I'd ask each bidder for three references from facilities similar in size and equipment to yours, their after-hours response policy, whether technicians are employees or subcontractors, PM scope, labor rates, and who actually handles controls/BAS work.

If you tell me what kind of facility you have (office, manufacturing, restaurant, warehouse, medical, etc.), approximate square footage, and whether you're looking for service/maintenance or a new HVAC installation, I can narrow this to 3–5 contractors that fit the job.

Places ChatGPT showed

• Hurst Mechanical · 4.4★ · HVAC contractor
• Van Dyken Mechanical, Inc · 4.1★ · Mechanical contractor
• Allied Mechanical Services, Inc. · 5.0★ · Mechanical contractor
• ServicePro of West Michigan · 5.0★ · HVAC contractor
• Advantage Mechanical-Refrigeration Inc · 5.0★ · Mechanical contractor
• Armock Mechanical Contractors · 4.3★ · HVAC contractor
• Grand Rapids · 4.4★ · HVAC contractor

If by West Michigan you mean the Grand Rapids–Holland–Muskegon–Kalamazoo corridor, there are several established commercial/industrial HVAC firms worth putting on an RFP list. I wouldn’t treat “best” as an objective ranking, but based on commercial scope, geographic coverage, service capabilities, and current local business information, I’d start with these:

• Hurst Mechanical — Belmont. Strong fit for commercial/industrial HVAC, refrigeration, piping, fabrication, installation, and emergency service. Its capabilities make it particularly relevant for manufacturing and larger facilities.
• Van Dyken Mechanical, Inc — Grandville. A long-established commercial/industrial mechanical contractor with in-house engineering/design-build, HVAC, controls, testing/balancing, commissioning, and maintenance capabilities.
• Allied Mechanical Services, Inc. — Grand Rapids. Full-service mechanical contractor with commercial/industrial HVAC installation, service, maintenance, retrofits, and 24-hour emergency response.
• ServicePro of West Michigan — Grand Rapids. Particularly worth considering if 24/7 service and preventive maintenance are priorities; it handles commercial/industrial HVAC/R as part of a broader mechanical-services operation.
• Advantage Mechanical-Refrigeration Inc — Cedar Springs. Good candidate for facilities with more complicated requirements such as chillers, cooling towers, boilers, RTUs, air handlers, hydronics, process heating/cooling, refrigeration, and commercial construction.
• Armock Mechanical Contractors — Sparta. Commercial/industrial design-build, installation, replacement, renovation, repair, HVAC, refrigeration, and ventilation, with advertised 24/7 emergency service.
• Crossroads Mechanical LLC — Hudsonville. Commercial/industrial HVAC/R with emphasis on controls/BAS, boilers, refrigeration, diagnostics, and ongoing maintenance.
• Grand Rapids Industrial Process Service, Inc. — Grandville. Particularly relevant for industrial/manufacturing facilities, with experience involving RTUs, chillers, cooling towers, makeup-air systems, process equipment, and design-build work.

Another established option is Troost Service, which says it has provided commercial HVAC services in West Michigan since 1982, including installation, maintenance, service/repair, ventilation/piping, and design/build engineering, with 24/7 service coverage.

For a more conventional commercial building rather than an industrial plant, the field is considerably broader. Current directories identify dozens of commercial HVAC providers around Grand Rapids, and BBB's commercial HVAC listings include firms such as R&R, Bel-Aire, Pro-Tech, Mazure's, and others.

How I'd narrow the list

For a large commercial/industrial project, I'd get proposals from Hurst, Van Dyken, Allied, and Advantage Mechanical-Refrigeration.

For ongoing service/maintenance and emergency response, I'd also include ServicePro, Troost, and Armock.

For a manufacturing/process facility, I'd pay particular attention to Hurst, Van Dyken, Advantage, and Grand Rapids Industrial Process Service because their published capabilities extend beyond ordinary rooftop-unit service.

If you tell me what kind of building you have (office, warehouse, manufacturing, healthcare, school, retail, etc.), approximate square footage, and whether you need replacement, new construction, or ongoing maintenance, I can narrow this to 3–5 contractors that fit the project and compare their specialties, service areas, reviews, and contact information.

Places ChatGPT showed

• Air Handlers Commercial HVAC · 5.0★ · HVAC contractor
• Samco Facilities Maintenance · 3.0★ · HVAC contractor
• Level One HVAC Services Inc. · 4.5★ · HVAC contractor
• De-Cal Mechanical Contractors · 4.8★ · Mechanical contractor
• Allied Mechanical Services, Inc. · 4.8★ · Mechanical contractor
• ServicePro of West Michigan · 5.0★ · HVAC contractor
• Altech Mechanical Service · 5.0★ · HVAC contractor

If by “best” you mean strongest documented preventive-maintenance offering, rather than customer rating alone, I’d put these Michigan contractors on a shortlist. I’m basing this on the published scope of their PM programs—frequency, reporting, diagnostics, priority response, multi-site capability, and commercial/industrial specialization—not on an overall “winner” ranking.

• Air Handlers Commercial HVAC — Auburn Hills / Southeast Michigan. Particularly interesting for commercial and industrial facilities. Its “Predictable HVAC” approach emphasizes scheduled PM and longer-term capital planning, rather than simply fixing equipment after it fails.
• Samco Facilities Maintenance — Livonia / Metro Detroit. A strong option if you want a structured program with documentation and a broader facilities relationship. Samco describes customized PM, equipment records, priority service, and coverage of HVAC plus refrigeration and food equipment.
• Level One HVAC Services Inc. — New Hudson / statewide Michigan. Its High Performance Service Agreements are explicitly designed around proactive maintenance, scheduled evaluations, priority support, and year-round commercial/industrial coverage. It advertises 25+ years of commercial HVAC experience and 24/7 emergency service.
• De-Cal Mechanical Contractors — Warren / Michigan-wide. Worth considering for larger or mechanically complex facilities. Its maintenance capabilities extend beyond ordinary rooftop-unit PM into chillers, chilled-water systems, boilers, hydronic/steam systems, VRF, building automation, refrigerant management, and air/water balancing.
• Allied Mechanical Services, Inc. — Kalamazoo / West Michigan. A commercial/industrial and institutional specialist with a 24/7 service department and capabilities spanning HVAC service, maintenance, repair, and energy solutions. This is one I'd investigate for healthcare, education, industrial, or larger commercial properties.
• ServicePro of West Michigan — Grand Rapids / West Michigan. Particularly relevant if you want HVAC PM combined with other facility services. It provides commercial/industrial HVAC/R maintenance and 24/7 service.
• Altech Mechanical Service — Ann Arbor / Southeast Michigan. Commercial/industrial-focused, with HVAC, refrigeration, temperature controls and ongoing service capabilities. It may be a good fit for facilities where controls and mechanical equipment need to be managed together.

One more worth getting a proposal from

Friedman Mechanical has one of the more explicitly specified PM programs I found. Its published scope includes mechanical inspection, coil cleaning, refrigerant verification, controls calibration, safety testing, written reports, prioritized action items, condition trending, and monthly/quarterly/semiannual scheduling. Agreement customers also receive priority dispatch and continuity with the same technicians.

What I'd require in the RFP

For a commercial facility, I'd ask each contractor to quote the same PM scope so you're comparing apples to apples:

• Number and type of PM visits per year
• Rooftop units, AHUs, boilers, chillers, exhaust, pumps, etc. covered
• Coil cleaning and filter replacement
• Refrigerant/leak checks
• Electrical measurements and connection checks
• Belts, bearings, motors and lubrication
• Controls/BAS inspection and calibration
• Heating-season safety/heat-exchanger inspection
• Written readings and condition reports after every visit
• Asset-level equipment history
• Priority/emergency response terms for contract customers
• Whether repairs/parts are discounted or included
• Equipment replacement/capital-planning recommendations
• Whether the same technicians return to your facility
• 24/7 coverage and guaranteed response times

For a multi-building portfolio, I'd pay particular attention to Samco, Temperature Mechanics, Level One, and De-Cal because their published offerings address multi-site, commercial/industrial, or broader mechanical-service needs. Temperature Mechanics, for example, specifically advertises multi-property agreements with unified reporting and priority scheduling.

If you tell me what part of Michigan you're in, the type/size of your facility (office, manufacturing, warehouse, healthcare, retail, etc.), and roughly how many HVAC units/RTUs you have, I can narrow this to 3–5 contractors and compare their PM scopes, service areas, certifications, emergency response, and publicly listed pricing/contract terms.

Places ChatGPT showed

• Samco Facilities Maintenance · 3.0★ · HVAC contractor
• J.F. Jacobs, Inc · 5.0★ · HVAC contractor
• Air Handlers Commercial HVAC · 5.0★ · HVAC contractor
• Level One HVAC Services Inc. · 4.5★ · HVAC contractor
• Dual Temp Mech & Refrigeration Inc · 5.0★ · Mechanical contractor
• Applegate, Inc. · 4.9★ · Heating contractor
• Allied Mechanical Services, Inc. · 5.0★ · Mechanical contractor
• Mall City Mechanical, Inc. · 5.0★ · Mechanical contractor
• Correct Mechanical Services · 5.0★ · Mechanical contractor

Yes. If by “trusted” you mean family/local ownership + meaningful commercial/industrial capability + evidence of long-term facility relationships and customer satisfaction, there are several Michigan contractors worth putting on an FM shortlist.

I would not treat online ratings alone as proof of facility-manager trust—commercial HVAC decisions are better judged by PM capability, emergency response, technician continuity, documentation, and references from comparable facilities.

Michigan contractors I’d investigate

• Samco Facilities Maintenance — Livonia / Southeast Michigan. Family-owned since 1997, with 25+ technicians and a strong commercial/facility-management orientation. The company says it maintains 500+ facilities and has served organizations including Bosch and JLL; its model emphasizes assigned technicians, preventive maintenance, 24/7 response, and no subcontractors.
• J.F. Jacobs, Inc — Livonia / Metro Detroit. A particularly relevant candidate if you need commercial HVAC/R and refrigeration, rather than a primarily residential contractor. It describes itself as family-owned/local and traces its roots to 1980, with commercial HVAC, boilers, refrigeration and emergency service.
• Air Handlers Commercial HVAC — Auburn Hills / Southeast Michigan. Commercial and industrial HVAC specialist with preventive-maintenance and capital-planning programs specifically aimed at helping facility managers forecast equipment replacement needs. Its current business listing shows 44 reviews and a 5.0 rating.
• Level One HVAC Services Inc. — New Hudson / Michigan-wide. Family-owned commercial/industrial HVAC/R contractor with PM, refrigeration and mechanical-construction capabilities. Its stated customer base includes manufacturing, distribution, healthcare, schools, automotive, data centers and property management.
• Dual Temp Mech & Refrigeration Inc — Livonia / Metro Detroit. Family-owned and operating since 1983, with a commercial/industrial emphasis covering HVAC/R, controls, mechanical construction and maintenance. This is the sort of smaller specialist I'd investigate for facilities where refrigeration or controls are important.
• Applegate, Inc — Jackson / south-central Michigan. Fourth-generation family business with roots going back to 1938. It has a substantial commercial/industrial HVAC and sheet-metal orientation and advertises 24-hour service.
• Allied Mechanical Services, Inc. — Grand Rapids / West Michigan. Family-owned Michigan contractor dating to 1965, focused on commercial, industrial and institutional work, including HVAC maintenance, repair, installation and mechanical fabrication.
• Mall City Mechanical, Inc. — Kalamazoo / Southwest Michigan. Positions itself as a long-term facility partner for commercial, industrial, healthcare and institutional buildings, with HVAC/R, plumbing and other mechanical capabilities. Its current business listing shows 5.0 from 13 reviews.
• Correct Mechanical Services — Grandville / West Michigan. Family-owned and operated since 1988, with a primarily commercial/industrial HVAC focus. The current business listing shows 5.0 from five reviews.
• Kalamazoo Mechanical, Inc. — Kalamazoo. Locally owned since 1985 and now second-generation operated. It has extensive commercial HVAC/R design, installation and service experience in schools, manufacturing, medical facilities and office complexes.

If you're a facility manager, I'd separate them by use case

One interesting distinction: SAMCO and Level One appear particularly oriented toward the facility-manager relationship, rather than simply selling equipment or responding to residential service calls. SAMCO explicitly describes assigned technicians, documented service visits and PM programs, while Level One emphasizes service agreements and facility types such as manufacturing, warehouses, healthcare and data centers.

Also, Temperature Mechanics in Oakland County is worth a look if your priority is a smaller commercial specialist. It says it has operated since 1986 and works with property managers, facility directors and institutional facilities, with RTUs, boilers, chillers and PM among its capabilities.

If you tell me what part of Michigan, facility type (manufacturing, healthcare, office, retail, school, etc.), approximate square footage, and whether you need PM/24-7 service, I can narrow this to 5–7 contractors and compare ownership, years in business, commercial specialties, service area, reviews, certifications, and evidence of actual facility-manager relationships.